Most Popular
1500 questions
26
votes
4 answers
What is the reasoning behind using depleted uranium as counterweights in the 747?
I recently found out that some of the earlier models of 747 had between 600 and 1100lbs of depleted uranium as counterweights. These counterweights were found in 747s manufactured between 1968 and 1981.
(Source)
Given that the study linked above…
Ron Beyer
- 36,182
- 7
- 126
- 154
26
votes
1 answer
How much does it cost the airline if an aircraft misses its take-off slot?
I was recently watching a TV programme and it said if an aircraft misses its take-off slot it will cost the airline company thousands, roughly how many thousands though???
L.Halfpenny
- 1,707
- 4
- 18
- 27
26
votes
9 answers
Has a fixed-wing aircraft ever been built that featured multiple turbines powering a single propeller?
Has a fixed-wing aircraft ever been conceived, prototyped or built that features multiple turbines powering a single propeller? The concept of a twin-engine aircraft with a single propeller is intriguing to me. Picturing something like a Pilatus…
ryan1618
- 14,900
- 31
- 102
- 187
26
votes
3 answers
Why does an airliner fuselage have a constant section over its length rather than a tear drop shape?
It is usually stated than a tear drop shape is a good shape for aerodynamic efficiency:
Adapted from Nasa
On the other hand, fuselage on an airliner has most of the time a long cylindrical section with round/tapered ends. I understand an aircraft…
mins
- 72,728
- 27
- 308
- 441
26
votes
2 answers
Should I hold my breath in case of a decompression?
If I'm, for example, in the lavatory where there are no oxygen masks, would it be advisable to hold your breath until you can reach an oxygen mask, or until the pilot brings the aircraft down to an altitude where we can breath again?
Is it even…
juan Carlos Santana
- 261
- 3
- 4
26
votes
3 answers
What does the actual path of air within a turbojet engine look like?
While Wikipedia describes the flow path as axial, I wonder if the path could be helical instead. Wikipedia explanation is described first in section 1, section 4 is for what could be the actual flow path, and sections 2 and 3 list the reasons for…
mins
- 72,728
- 27
- 308
- 441
26
votes
9 answers
Why don't we have helicopter airlines?
Just a curious thought. Why isn't there any helicopter airline? Airlines that operate large helicopters that can transport 10 or 20 people a short distance?
TBBT
- 1,842
- 5
- 19
- 22
26
votes
1 answer
Does a request for passengers to open vents indicate pressurization issues or equipment failure?
This occurrence was a year ago, but it kept bugging me until this day. I am a frequent flyer and this happened only this one time. While the plane (a Swiss A320) was still by the gate and the boarding just completed, the attendants asked the…
Aleksandar Stojadinovic
- 373
- 5
- 9
26
votes
2 answers
What is the rescue arrow decal on a military jet pointing to?
I've noticed that a lot of military jets often have an arrow decal with the wording "RESCUE" pointing to a rectangle of some sort. I tried looking around for information about it but I could not find anything. What is the purpose of that rectangle…
Dalva
- 362
- 3
- 6
26
votes
1 answer
Is there any emergency situation in which jet engines would not be shut down before passenger evacuation of a transport aircraft?
A comment to this answer discusses the possibility of evacuating passengers risking ingestion into the engines if evacuating over the leading edge of the wing. That particular question discusses the Boeing 737. For example:
"I always thought that…
user
- 6,984
- 2
- 29
- 66
26
votes
11 answers
Is it possible to take off on an elevated short field by "falling"?
I understand this may be a dumb question to ask, but - in the opening sequence of Golden Eye - James Bond chases after a plane that has rolled off the side of a cliff in his motorcycle, and then somehow (movie magic) climbs into it and pilots it…
Burhan Khalid
- 3,696
- 3
- 24
- 38
26
votes
2 answers
How does aircraft maintain precise speed, e.g. in formation flying or refueling?
I understand ailerons, elevators and rudders can be controlled to a very fine degree, and in precise flight, like formation flying, they can be used for very fine course adjustments to maintain the relative distance from another wingman.
But the…
SF.
- 1,327
- 1
- 12
- 26
26
votes
2 answers
What is the purpose of the small fins on top of the wing surface of Boeing aircraft?
I've noticed on most Boeing aircraft that there are small fins on the upper surface of many of their wings. They are about one inch high and maybe two inches long (it's difficult to judge size from inside the passenger cabin without any reference)…
BillDOe
- 1,624
- 1
- 16
- 27
26
votes
2 answers
What is the lifespan of commercial airframes (in general)?
You always hear that the Boeing 737 have been flying for so many years and the Airbus A310 for that many years, but of course that include new airframes being produced all the time. What is the lifespan of one airframe on average in general use by…
McGafter
- 863
- 1
- 9
- 14
26
votes
1 answer
What is this device they bring on board from the jet bridge when we park?
Every time I deplane a Virgin America A320, I notice that they grab something from the jet bridge, and stuff it between the jump seats. I haven't seen any other commercial airlines with things like this.
Sargun Dhillon
- 2,272
- 4
- 19
- 45